Electric pump device

ABSTRACT

A motor, an inverter substrate electrically connected to the motor, a housing accommodating the motor and the inverter substrate, and a pump section driven by the motor are included. The inverter substrate is disposed on one side of the motor. The pump section is disposed on the other side of the motor. The housing has a motor housing section accommodating the motor, an inverter housing section accommodating the inverter substrate, and a breather section establishing communication between inside and outside of the housing. The motor housing section has an accommodation tubular section accommodating the motor and a brim section spreading outward in a radial direction from an end of the accommodation tubular section. The inverter housing section is disposed on one side of the brim section and overlaps the brim section when seen in the axial direction. The breather section is disposed at the brim section.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority of Japan patent application serialno. 2018-185863, filed on Sep. 28, 2018. The entirety of theabove-mentioned patent application is hereby incorporated by referenceherein and made a part of this specification.

BACKGROUND Technical Field

The present invention relates to an electric pump device.

Description of Related Art

An electric pump device includes a motor, a substrate, a housing, and apump. According to an electric pump unit disclosed in Patent literature1, a vent filter unit is incorporated in a thermosetting viscoelasticresin that forms a heat-discharging sealed layer. The vent filter unitcommunicates with external air through a hole formed in a lid.

According to Patent literature 1, there is a concern that water dropletsand the like flying from a road surface adheres directly to the ventfilter unit at the time of traveling of a vehicle or the like.

[Patent literature 1] Japanese Patent Laid-Open No, 2010-112328

SUMMARY

In view of the aforementioned circumstances, an objective of theinvention is to provide an electric pump device capable of curbingdirect adhesion of water droplets and the like flying due to travelingof a vehicle or the like to a breather section.

According to an aspect of the invention, there is provided an electricpump device including: a motor; an inverter substrate that iselectrically connected to the motor; a housing that accommodates themotor and the inverter substrate; and a pump section that is driven bymotive power of the motor, in which the motor has a rotor that has ashaft extending along a central axis, and a stator that faces the rotorin a radial direction, the inverter substrate is disposed on one side ofthe motor in an axial direction, the pump section is disposed on theother side of the motor in the axial direction, the housing has a motorhousing section that accommodates the motor, an inverter housing sectionthat accommodates the inverter substrate, and a breather section thatestablishes communication between inside and outside of the housing, themotor housing section has an accommodation tubular section thataccommodates the motor, and a brim section that spreads outward in theradial direction from an end of the accommodation tubular section on oneside in the axial direction, the inverter housing section is disposed onone side of the brim section in the axial direction and overlaps thebrim section when seen in the axial direction, and the breather sectionis disposed at the brim section.

According to the electric pump device of the aspect of the invention, itis possible to curb direct adhesion of water droplets and the likeflying due to traveling of a vehicle or the like to the breathersection.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a motor unit and an electricpump device according to an embodiment.

FIG. 2 is a front view illustrating the motor unit and the electric pumpdevice according to the embodiment.

FIG. 3 is a vertical sectional view illustrating a section taken alongIII-III in FIG. 2.

FIG. 4 is a back view (plan view) illustrating the motor unit and theelectric pump device according to the embodiment and illustrates a statein which a first member and the like of an inverter housing section havebeen removed from the device.

FIG. 5 is a vertical sectional view illustrating a section taken alongV-V in FIG. 4.

FIG. 6 is a vertical sectional view illustrating a section taken alongVI-VI in FIG. 4.

FIG. 7 is a back view illustrating the motor unit and the electric pumpdevice according to the embodiment and illustrates a state in which theinverter housing section, the inverter substrate, and the like have beenremoved from the device.

FIG. 8 is a vertical sectional view illustrating a section taken alongVIII-VIII in FIG. 7.

FIG. 9 is a side view schematically illustrating a portion near a firstend of a coil.

FIG. 10 is a plan view illustrating a modification example of the heatconductive sheet.

DESCRIPTION OF EMBODIMENTS

A motor unit 10 and an electric pump device 1 provided with the motorunit 10 according to an embodiment of the invention will be describedwith reference to drawings. In the drawings, XYZ coordinate systems willbe appropriately illustrated as three-dimensional orthogonal coordinatesystems. The motor unit 10 and the electric pump device 1 include amotor 20 and an inverter substrate 40. The motor 20 has a central axisJ, and the central axis J extends along a Z-axis direction. In thefollowing description, the direction parallel to the central axis J willbe simply referred to as an “axial direction” unless otherwiseparticularly stated. The position of the motor 20 in the axial directionand the position of the inverter substrate 40 in the axial direction aredifferent from each other. That is, the motor 20 and the invertersubstrate 40 are aligned in the axial direction. In the axial direction,a direction from the motor 20 toward the inverter substrate 40 will bereferred to as toward one side (+Z side) in the axial direction, and adirection from the inverter substrate 40 toward the motor 20 will bereferred to as toward the other side (−Z side) in the axial direction.The radial direction around the central axis J will be simply referredto as a “radial direction”. In the radial direction, a direction towardthe central axis J will be referred to as inward in the radialdirection, and a direction away from the central axis J will be referredto as outward in the radial direction. A circumferential directionaround the central axis J, that is, turning around the central axis Jwill be simply referred to as a “circumferential direction”. Also, a“parallel direction” includes a substantially parallel direction, and an“orthogonal direction” includes a substantially orthogonal direction, inthe embodiment.

The electric pump device 1 according to the embodiment suctions andejects a fluid such as an oil, for example. The electric pump device 1has a function of circulating the fluid through a flow path, forexample. In a case in which the fluid is an oil, the electric pumpdevice 1 may be referred to as an electric oil pump device instead.Although not particularly illustrated in the drawing, the electric pumpdevice 1 is provided in a drive device or the like of a vehicle, forexample. That is, the electric pump device 1 is mounted in the vehicle.

As illustrated in FIGS. 1 to 9, the motor unit 10 includes a housing 11,fastening screws 18, fixing screws 19, a motor 20, an inverter substrate40, wiring members 50, screw members 60, and a coil support 80. Theelectric pump device 1 includes a motor unit 10, a pump section 90, anda pump cover 95. That is, the electric pump device 1 includes thehousing 11, the fastening screws 18, the fixing screws 19, the motor 20,the inverter substrate 40, the wiring members 50, the screw members 60,the coil support 80, the pump section 90, and the pump cover 95. In theembodiment, a pair of plate surfaces of the inverter substrate 40 aredirected in the axial direction. One plate surface of the pair of platesurfaces of the inverter substrate 40 is directed to one side in theaxial direction. The other plate surface of the pair of plate surfacesof the inverter substrate 40 is directed to the other side in the axialdirection. In the embodiment, “when seen in the axial direction” has thesame meaning as that of “in a plan view of the inverter substrate 40”.

The housing 11 accommodates the motor 20 and the inverter substrate 40.The housing 11 has a motor housing section 12, an oil seal 32, an axissection 33, an inverter housing section 13, a breather section 14. Themotor housing section 12 accommodates the motor 20. In the embodiment,the motor housing section 12 also accommodates the pump section 90. Thatis, the housing 11 also accommodates the pump section 90. In theembodiment, since the motor 20 and the pump section 90 are accommodatedin the motor housing section 12, the structure of the electric pumpdevice 1 can be simplified. Assembly of the electric pump device 1 isfacilitated.

The motor housing section 12 is made of metal. The motor housing section12 is made of a single member. The motor housing section 12 has anaccommodation tubular section 12 a, a brim section 12 b, a pumpaccommodation wall section 12 c, a bearing holding tubular section 12 d,and pillar sections 12 g.

The accommodation tubular section 12 a has a tubular shape extending inthe axial direction. In the embodiment, the accommodation tubularsection 12 a has a cylindrical shape. The accommodation tubular section12 a accommodates the motor 20. The brim section 12 b spreads from theend of the accommodation tubular section 12 a on one side in the axialdirection outward in the radial direction. The brim section 12 b has aplate shape with a plate surface directed in the axial direction. In theembodiment, the outer shape of the brim section 12 b is a substantiallypolygonal shape when seen in the axial direction.

The brim section 12 b has a breather attachment hole 12 i, a breatheraccommodation recessed section 12 j, a claw support surface 12 k, anouter surrounding surface 12 l, and an axis section attachment hole 12 m(see FIGS. 5 and 6). The breather attachment hole 12 i penetratesthrough the brim section 12 b in the axial direction. The breatherattachment hole 12 i has a portion with a tapered hole shape with aninner diameter increasing toward the other side in the axial direction.The breather attachment hole 12 i overlaps a wiring member dispositionregion 13 a, which will be described later, when seen in the axialdirection.

The breather accommodation recessed section 12 j is recessed on one sidein the axial direction from the surface of the brim section 12 bdirected to the other side in the axial direction. The breatheraccommodation recessed section 12 j has a circular ring shape when seenin the axial direction. The inner diameter of the breather accommodationrecessed section 12 j is greater than the inner diameter of the breatherattachment hole 12 i. The bottom surface of the breather accommodationrecessed section 12 j directed to the other side in the axial directionis continuous with the inner circumferential surface of the breatherattachment hole 12 i.

The claw support surface 12 k is disposed on the surface of the brimsection 12 b directed to one side in the axial direction. In theembodiment, the claw support surface 12 k is a plane perpendicular tothe central axis J. The claw support surface 12 k has a substantiallyannular shape when seen in the axial direction and surrounds thebreather attachment hole 12 i from the outside (see FIG. 7). The innercircumferential portion of the claw support surface 12 k is continuouswith the end (opening) of the breather attachment hole 12 i on one sidein the axial direction.

The outer surrounding surface 12 l is disposed in the surface of thebrim section 12 b directed to one side in the axial direction. The outersurrounding surface 12 l has substantially a C shape when seen in theaxial direction. The outer surrounding surface 12 l surrounds the clawsupport surface 12 k from the breather radial direction when seen in theaxial direction. Also, the breather radial direction is a radialdirection around the breather central axis C as will be described later.The outer surrounding surface 12 l is located on the other side in theaxial direction beyond the claw support surface 12 k. That is, theposition of the outer surrounding surface 12 l in the axial direction islocated on the other side in the axial direction beyond the position ofthe claw support surface 12 k in the axial direction.

The axis section attachment hole 12 m is recessed on the other side inthe axial direction from the surface of the brim section 12 b on oneside in the axial direction. The axis section attachment hole 12 mextends in the axial direction. The axis section attachment hole 12 mhas a circular hole shape.

The pump accommodation wall section 12 c is disposed at an end of theaccommodation tubular section 12 a on the other side in the axialdirection. The pump accommodation wall section 12 c is disposed in theaccommodation tubular section 12 a. The pump accommodation wall section12 c blocks an opening in the accommodation tubular section 12 a on theother side in the axial direction. The pump accommodation wall section12 c has a plate shape with a plate surface directed in the axialdirection. In the embodiment, the pump accommodation wall section 12 chas a substantially circular plate shape. The pump accommodation wallsection 12 c accommodates the pump section 90. The pump accommodationwall section 12 c has a pump accommodation hole 12 f and a plurality oflightening holes (not illustrated).

The pump accommodation hole 12 f is recessed on one side in the axialdirection from the plate surface of the pump accommodation wall section12 c directed to the other side in the axial direction. In theembodiment, the pump accommodation hole 12 f has a circular hole shape.The pump accommodation hole 12 f is disposed at the center of the pumpaccommodation wall section 12 c when seen in the axial direction.Although not particularly illustrated in the drawing, the plurality oflightening holes are recessed on the other side in the axial directionfrom the plate surface of the pump accommodation wall section 12 cdirected to one side in the axial direction and are disposed atintervals from each other in the circumferential direction. Theplurality of lightening holes are disposed outward from the pumpaccommodation hole 12 f in the radial direction.

The bearing holding tubular section 12 d has a tubular shape extendingon one side in the axial direction from the pump accommodation wallsection 12 c. The bearing holding tubular section 12 d projects on oneside in the axial direction from the plate surface of the pumpaccommodation wall section 12 c directed to one side in the axialdirection. The bearing holding tubular section 12 d holds a firstbearing 35, which will be described later, of the motor 20. The firstbearing 35 is a bearing located on the other side of a rotor core 23,which will be described later, in the axial direction among theplurality of bearings 35 and 36 disposed in the motor 20 at intervalsfrom each other in the axial direction. The first bearing 35 is fittedinto the bearing holding tubular section 12 d.

The pillar sections 12 g extend in the axial direction. The pillarsections 12 g are disposed at the brim section 12 b and extend on oneside in the axial direction from the brim section 12 b. The pillarsections 12 g project on one side in the axial direction from the platesurface of the brim section 12 b directed to one side in the axialdirection. The number of pillar sections 12 g provided is a pluralnumber. The plurality of pillar sections 12 g are disposed at intervalsfrom each other in the circumferential direction when seen in the axialdirection. Specifically, the plurality of pillar sections 12 g aredisposed at intervals from each other at positions at which the pillarsections 12 g overlap an outer circumferential portion of the invertersubstrate 40 when seen in the axial direction, that is, in a plan viewof the inverter substrate 40.

In the embodiment, the pillar sections 12 g have substantiallycylindrical shapes. The pillar sections 12 g have outer diametersdecreasing toward one side in the axial direction. The outercircumferential surfaces of the pillar sections 12 g have taperedshapes. The pillar sections 12 g have female screw sections in the innercircumferential surfaces of the pillar sections 12 g. End surfaces ofthe pillar sections 12 g directed to one side in the axial directionhave plane shapes perpendicular to the central axis J. The end surfacesof the pillar sections 12 g directed to one side in the axial directionare brought into contact with the plate surface of the invertersubstrate 40 directed to the other side in the axial direction.

The pillar sections 12 g are disposed in the inverter housing section13. The pillar sections 12 g extend inside the inverter housing section13. The pillar sections 12 g are fixed to the inverter substrate 40.According to the embodiment, since the inverter substrate 40 is fixed tothe pillar sections 12 g of the motor housing section 12, it is possibleto enhance an attachment rigidity of the inverter substrate 40 withrespect to the housing 11 and to improve vibration damping properties ofthe inverter substrate 40. It is possible to curb relative vibrationbetween the stator 26, which will be described later, fixed to the motorhousing section 12 through thermal fitting or the like and the invertersubstrate 40. Therefore, it is possible to enhance durability of asolder 30 that fixes first ends 29 a of the coils 29, which will bedescribed later, of the stator 26 and the inverter substrate 40. Inaddition, it is also possible to enhance durability of a solder 31 thatfixes terminals 51, which will be described later, of the wiring members50 and the inverter substrate 40.

Also, according to the embodiment, the pillar sections 12 g extend inthe axial direction from the brim section 12 b that is located outwardin the radial direction beyond the accommodation tubular section 12 aand support the inverter substrate 40. Therefore, the pillar sections 12g can stably support the inverter substrate 40 even if the invertersubstrate 40 has a larger outer shape than that of the accommodationtubular section 12 a.

In addition, according to the embodiment, the inverter substrate 40 ismore stably supported with the plurality of pillar sections 12 g. Also,since the pillar sections 12 g are disposed at the outer circumferentialportion of the inverter substrate 40, an influence on a degree offreedom in a wiring pattern of the inverter substrate 40 is curbed.Also, since the motor housing section 12 is made of metal, it ispossible to further improve vibration damping properties of the invertersubstrate 40 with the motor housing section 12 with high rigidity.

In addition, according to the embodiment, since the pillar sections 12 gare a part of the motor housing section 12 made of a single member, thatis, the pillar sections 12 g are provided integrally with the motorhousing section 12, satisfactory sealing properties around the pillarsections 12 g can be maintained. Therefore, invasion of water and thelike from the outside of the device to the inside of the motor housingsection 12 and the inverter housing section 13 through the circumferenceof the pillar sections 12 g can be curbed. Configurations, effects, andadvantages of the pillar sections 12 g other than those described abovewill be separately described below with description of the inverterhousing section 13.

The oil seal 32 has an annular shape around the central axis J. The oilseal 32 is disposed in the bearing holding tubular section 12 d and islocated on the other side in the axial direction beyond the firstbearing 35. The axis section 33 is a pin member extending in the axialdirection. The axis section 33 is fitted into the axis sectionattachment hole 12 m. The axis section 33 projects on one side in theaxial direction from the brim section 12 b.

The inverter housing section 13 accommodates the inverter substrate 40.In the embodiment, the inverter housing section 13 also accommodates thecoil support 80. That is, the housing 11 also accommodates the coilsupport 80. The inverter housing section 13 is disposed on one side ofthe brim section 12 b in the axial direction and overlaps the brimsection 12 b when seen in the axial direction. The inverter housingsection 13 has a first member 16, a second member 17, and heatconductive sheets 13 c. Also, the inverter housing section 13 has awiring member disposition region 13 a and a coil support accommodationspace 13 b.

The first member 16 may be referred to as a lid member of the inverterhousing section 13 instead. The first member 16 is made of metal. Thefirst member 16 is disposed on one side of the inverter substrate 40 inthe axial direction and covers the inverter substrate 40 on one side inthe axial direction. The first member 16 faces one plate surface of thepair of plate surfaces of the inverter substrate 40. The first member 16faces one plate surface directed to one side of the inverter substrate40 in the axial direction with a gap interposed therebetween in theaxial direction. The first member 16 has a capped tubular shape.

The first member 16 has a top wall 16 a, a circumferential wall 16 b,and a flange 16 c. The top wall 16 a faces one plate surface of theinverter substrate 40. The circumferential wall 16 b has a tubular shapeextending on the other side in the axial direction from the outercircumferential portion of the top wall 16 a. The circumferential wall16 b is disposed in a superimposed manner on the inverter substrate 40when seen in the radial direction. The flange 16 c spreads outward inthe radial direction from an end of the circumferential wall 16 b on theother side in the axial direction.

The second member 17 may be referred to as a main body member of theinverter housing section 13 instead. The second member 17 is locatedbetween the motor housing section 12 and the first member 16 in theaxial direction. That is, the second member 17 is disposed between themotor housing section 12 and the first member 16. The second member 17is fixed to the brim section 12 b. The second member 17 is sandwichedbetween the brim section 12 b and the flange 16 c in the axial directionand is fixed with the fastening screws 18. The number of fasteningscrews 18 provided is a plural number. The plurality of fastening screws18 are disposed at intervals from each other in the circumferentialdirection. According to the embodiment, since the second member 17 isfixed to the brim section 12 b, it is possible to secure a wide regionfor fixing the inverter housing section 13 to the motor housing section12 and to stably fix the inverter housing section 13 to the motorhousing section 12. Also, it is possible to secure an inner volume ofthe inverter housing section 13 and to reduce the inverter housingsection 13 in size in the axial direction.

The second member 17 is disposed on the other side of the invertersubstrate 40 in the axial direction and covers the inverter substrate 40on the other side in the axial direction. The second member 17 faces theother plate surface of the pair of plate surfaces of the invertersubstrate 40. The second member 17 faces the other plate surfacedirected to the other side of the inverter substrate 40 in the axialdirection with a gap therebetween in the axial direction. The secondmember 17 has a tubular shape with a bottom.

The second member 17 has a bottom wall 17 a and a circumferential wall17 b. That is, the inverter housing section 13 has a bottom wall 17 aand a circumferential wall 17 b. The bottom wall 17 a faces the otherplate surface of the inverter substrate 40. That is, the bottom wall 17a faces the plate surface, which is directed to the other side in theaxial direction, of the pair of plate surfaces of the inverter substrate40. The bottom wall 17 a has a plate shape with a plate surface directedin the axial direction. The bottom wall 17 a is fixed to the brimsection 12 b with fixing screws 19. That is, the second member 17 isfixed to the motor housing section 12 with the fixing screws 19. Thenumber of fixing screws 19 provided is a plural number. The plurality offixing screws 19 are disposed at intervals from each other in thecircumferential direction. The fixing screws 19 are used for the purposeof temporarily fixing the second member 17 to the motor housing section12 until the inverter housing section 13 and the motor housing section12 are fastened with the fastening screws 18. Also, the temporary fixingindicates a temporary fixing state that is required for assembly. Thenumber of fixing screws 19 is smaller than the number of fasteningscrews 18. Since the second member 17 is fixed to the motor housingsection 12 with the fixing screws 19, relative positions between theinverter substrate 40 fixed to the pillar sections 12 g of the motorhousing section 12 and the terminals 51 of the wiring members 50 held bya connector section 17 i, which will be described later, of the secondmember 17 are stabilized, and connection of the terminals 51 to theinverter substrate 40 is facilitated.

The bottom wall 17 a has a bearing holder 17 c, a waved washer 17 g, afitting tubular section 17 d, through-holes 17 e, rib sections 17 f, apin section 71, a boss section 17 j, an insertion hole 17 k, a breatheraccommodation wall 17 l, and a tubular disposition hole 17 m. That is,the second member 17 has a bearing holder 17 c, through-holes 17 e, anda boss section 17 j. In addition, the pin section 71 is provided at theinverter housing section 13.

The bearing holder 17 c is made of metal. When the second member 17 isinjection-molded, the bearing holder 17 c is disposed in a mold, whichis not illustrated, along with other metal components. By filling themold with a molten resin and solidifying the resin, the second member 17is insert-molded along with the bearing holder 17 c. That is, the secondmember 17 has a portion made of the resin. According to the embodiment,since the second member 17 has the portion made of the resin, a degreeof freedom in the shape of the second member 17 increases. Therefore, itis possible to easily provide the connector section 17 i and the like,which will be described later, on the second member 17.

The bearing holder 17 c has a capped tubular shape. The bearing holder17 c holds at least one bearing 36 of the plurality of bearings 35 and36, which will be described later, of the motor 20. The bearing holder17 c holds the second bearing 36. The second bearing 36 is a bearinglocated on one side of the rotor core 23, which will be described later,in the axial direction among the plurality of bearings 35 and 36. Thesecond bearing 36 is fitted into the bearing holder 17 c.

The waved washer 17 g has an annular shape around the central axis J.The waved washer 17 g is disposed in the bearing holder 17 c and islocated between the top wall of the bearing holder 17 c and the secondbearing 36 in the axial direction. The waved washer 17 g is brought intocontact with the top wall of the bearing holder 17 c and the secondbearing 36 in the axial direction. The waved washer 17 g biases thebearing holder 17 c and the second bearing 36 in a direction in whichthe bearing holder 17 c and the second bearing 36 are separated fromeach other in the axial direction.

The fitting tubular section 17 d has a tubular shape extending on theother side in the axial direction from the bottom wall 17 a. The fittingtubular section 17 d is fitted into the accommodation tubular section 12a. In the embodiment, the fitting tubular section 17 d has a cylindricalshape and is fitted to the inside of the end (opening) of theaccommodation tubular section 12 a on one side in the axial direction.According to the embodiment, the bearing 36 held by the bearing holder17 c of the bottom wall 17 a is positioned coaxially with the centralaxis J of the shaft 22 by the fitting tubular section 17 d of the bottomwall 17 a being fitted into the accommodation tubular section 12 a ofthe motor housing section 12. Therefore, performance of the motor 20 isstabilized.

The through-holes 17 e penetrate through the bottom wall 17 a in theaxial direction. In the embodiment, the through-holes 17 e have circularhole shapes. The number of through-holes 17 e provided is a pluralnumber. The plurality of through-holes 17 e are disposed at intervalsfrom each other in the circumferential direction when seen in the axialdirection. Specifically, the plurality of through-holes 17 e aredisposed at intervals from each other at positions at which thethrough-holes 17 e overlap the outer circumferential portion of theinverter substrate 40 when seen in the axial direction, that is, in aplan view of the inverter substrate 40. The pillar sections 12 g areinserted into the respective through-holes 17 e. That is, the pillarsections 12 g are inserted into the through-holes 17 e. According to theembodiment, it is possible to secure sealing properties between theinverter housing section 13 and the motor housing section 12 by causingthe pillar sections 12 g to pass through the through-holes 17 e of thesecond member 17. Also, it is possible to roughly position the inverterhousing section 13 and the motor housing section 12, which improvesassembling properties.

Now, the pillar sections 12 g will be described. The pillar sections 12g penetrate through the second member 17. The pillar sections 12 gpenetrate through the bottom wall 17 a of the second member 17 in theaxial direction. According to the embodiment, it is possible to disposethe pillar sections 12 g inside the inverter housing section 13 with asimple configuration. Also, it is possible to support the invertersubstrate 40 with the pillar sections 12 g. The pillar sections 12 g aredisposed inside the circumferential wall 17 b when seen in the axialdirection. The pillar sections 12 g project to one side in the axialdirection beyond the circumferential wall 17 b when seen in the radialdirection. According to the embodiment, the inverter substrate 40supported at a tip ends of the pillar sections 12 g is disposed on oneside in the axial direction beyond the circumferential wall 17 b of thesecond member 17. That is, the other plate surface of the invertersubstrate 40 is located on one side in the axial direction beyond thecircumferential wall 17 b. Therefore, it is possible to easily see, fromthe radial direction, whether or not the solders 30 and 31 haveappropriately reached the other plate surface of the inverter substrate40, that is, whether or not soldering has successfully been performed atthe time of soldering of the first ends 29 a of the coils 29, which willbe described later, and the terminals 51 to the inverter substrate 40.

The rib sections 17 f project on one side in the axial direction fromthe plate surface of the bottom wall 17 a directed to one side in theaxial direction and extend along a virtual plane, which is notillustrated in the drawing, perpendicular to the central axis J. Thenumber of rib sections 17 f provided is a plural number. The pluralityof rib sections 17 f radially extend around the central axis J. In theembodiment, the plurality of rib sections 17 f include rib sections 17 fextending in the radial direction and rib sections 17 f extending indirections other than the radial direction when seen in the axialdirection. The plurality of rib sections 17 f are disposed at intervalsfrom each other in the circumferential direction. Ends of the ribsections 17 f on the outside in the radial direction are connected tothe circumferential wall 17 b. End surfaces of the rib sections 17 fdirected to one side in the axial direction are located on the otherside in the axial direction beyond the end surface of thecircumferential wall 17 b directed to one side in the axial direction.

The pin section 71 extends in the axial direction. The pin section 71extends on one side in the axial direction from the bottom wall 17 a. Inthe embodiment, the pin section 71 is provided integrally with one ribsection 17 f among the plurality of rib sections 17 f. That is, the pinsection 71 and the one rib section 17 f are a portion of a singlemember. The pin section 71 is located between an inner end in the radialdirection and an outer end in the radial direction of the one ribsection 17 f.

The pin section 71 is inserted into a positioning hole 43, which will bedescribed later, of the inverter substrate 40. An end of the pin section71 on one side in the axial direction is inserted into the positioninghole 43. The end of the pin section 71 on one side in the axialdirection projects to one side in the axial direction beyond the endsurfaces of the pillar sections 12 g on one side in the axial direction.The pin section 71 faces at least one pillar section 12 g from among theplurality of pillar sections 12 g with a gap therebetween when seen inthe axial direction. That is, the pin section 71 is disposed to approachat least one pillar section 12 g with a gap therebetween when seen inthe axial direction. The pin section 71 has an outer diameter decreasingin a stepwise manner from the bottom wall 17 a toward one side in theaxial direction. According to the embodiment, it is possible to positionthe inverter substrate 40 and the inverter housing section 13 by the pinsection 71 being inserted into the positioning hole 43 of the invertersubstrate 40. Also, it is possible to curb rotation of the invertersubstrate 40 along with the screw members 60 when the inverter substrate40 is fixed to the pillar sections 12 g with the screw members 60, andthe inverter substrate 40 is prevented from rotating relative to theinverter housing section 13.

The boss section 17 j projects from the bottom wall 17 a toward one sidein the axial direction. The boss section 17 j extends in the axialdirection. The boss section 17 j has a tubular shape or a columnarshape. In the embodiment, the boss section 17 j has a cylindrical shape.A tip end surface of the boss section 17 j directed on one side of theboss section 17 j in the axial direction has a plane shape perpendicularto the central axis J. The tip end surface of the boss section 17 j isbrought into contact with the other plate surface of the invertersubstrate 40 or faces the other plate surface of the inverter substrate40 with a gap therebetween. The boss section 17 j can support the otherplate surface of the inverter substrate 40. The boss section 17 j isdisposed at the center of the inverter substrate 40 in a plan view ofthe inverter substrate 40. The bearing holder 17 c and the boss section17 j are disposed in a superimposed manner in a plan view of theinverter substrate 40.

The insertion hole 17 k is recessed on one side in the axial directionfrom the surface of the bottom wall 17 a directed to the other side inthe axial direction. The insertion hole 17 k extends in the axialdirection. The insertion hole 17 k overlaps the axis section attachmenthole 12 m and the axis section 33 when seen in the axial direction. Theaxis section 33 is inserted into the insertion hole 17 k. According tothe embodiment, the second member 17 is positioned in the radialdirection relative to the motor housing section 12 by the fittingtubular section 17 d being fitted into the accommodation tubular section12 a. Also, relative positions between the motor housing section 12 andthe inverter housing section 13 are stably determined, and connection ofthe first ends 29 a of the coils 29, which will be described later, andthe terminals 51 to the inverter substrate 40 is facilitated by the axissection 33 being inserted into the insertion hole 17 k, therebypositioning the second member 17 in the circumferential directionrelative to the motor housing section 12. Also, the axis section 33 andthe pin section 71 are disposed in a superimposed manner when seen inthe axial direction. According to the embodiment, since the axis section33 and the pin section 71 are coaxially disposed, it is possible to savespace for a positioning structure using these components.

The breather accommodation wall 17 l is recessed on one side in theaxial direction from the surface of the bottom wall 17 a directed to theother side in the axial direction. The breather accommodation wall 17 lhas a capped tubular shape. The breather accommodation wall 17 l has acircumferential wall and a top wall. The circumferential wall of thebreather accommodation wall 17 l extends from the bottom wall 17 atoward one side in the axial direction. The top wall of the breatheraccommodation wall 17 l blocks an opening in the circumferential wall ofthe breather accommodation wall 17 l on one side in the axial direction.The breather accommodation wall 17 l overlaps the breather attachmenthole 12 i when seen in the axial direction. The tubular disposition hole17 m penetrates through the bottom wall 17 a in the axial direction.Extending tubular sections 85 b, which will be described later, of thecoil support 80 are disposed inside the tubular disposition hole 17 m.

The circumferential wall 17 b has a tubular shape extending on one sidein the axial direction from an outer circumferential portion of thebottom wall 17 a. In the embodiment, the circumferential wall 17 b has asubstantially polygonal tubular shape. The circumferential wall 17 b hasspacers 17 h and a connector section 17 i. That is, the inverter housingsection 13 has a connector section 17 i.

The spacers 17 h have tubular shapes extending in the axial direction.In the embodiment, the spacers 17 h have cylindrical shapes. The spacers17 h are provided on the circumferential wall 17 b and penetrate throughthe second member 17 in the axial direction. The number of spacers 17 hprovided is a plural number. The plurality of spacers 17 h are disposedat intervals from each other in the circumferential direction. Thefastening screws 18 are inserted into the respective spacers 17 h. Thespacers 17 h are made of metal. When the second member 17 isinjection-molded, the spacers 17 h are disposed in a mold, which is notillustrated in the drawings, along with other metal components. Thesecond member 17 is insertion-molded along with the spacers 17 h byfilling the mold with a molten resin and solidifying the resin.

An external power source, which is not illustrated in the drawing, isconnected to the connector section 17 i. The connector section 17 i hasa tubular shape. In the embodiment, the connector section 17 i has asquare tubular shape. The connector section 17 i extends from thecircumferential wall 17 b outward from the circumferential wall 17 bwhen seen in the axial direction. The connector section 17 i projectsoutward from the circumferential wall 17 b along a virtual plane, whichis not illustrated in the drawing, perpendicular to the central axis J.In the embodiment, the direction in which the connector section 17 iprojects from the circumferential wall 17 b will be referred to as aprojecting direction in some cases. The projecting direction of theconnector section 17 i corresponds to toward the +X side. The sideopposite to the projecting direction corresponds to toward the X side.Also, a direction orthogonal to the projecting direction when seen inthe axial direction will be referred to as a width direction in somecases. The width direction is a Y-axis direction. The connector section17 i is disposed at a position that is different from that of thecentral axis J in the width direction. In the width direction, thedirection from the central axis J toward the connector section 17 i willbe referred to as toward one side (+Y side) in the width direction, andthe direction from the connector section 17 i toward the central axis Jwill be referred to as toward the other side (−Y side) in the widthdirection.

The connector section 17 i and the circumferential wall 17 b are aportion of a single member. A part of the wiring members 50 is disposedinside the connector section 17 i. The connector section 17 i is fixedto the wiring members 50. The connector section 17 i holds the wiringmembers 50.

The wiring member disposition region 13 a is a space in which the wiringmembers 50 are disposed in the inverter housing section 13. The wiringmember disposition region 13 a is located between the central axis J andthe connector section 17 i in the projecting direction in a plan view ofthe inverter substrate 40 in the inner space of the inverter housingsection 13. That is, the wiring member disposition region 13 a islocated between the central axis J and the connector section 17 i whenseen in the axial direction. The wiring member disposition region 13 ais located in the projecting direction (+X side) beyond the central axisJ and is located on the side (−X side) opposite to the projectingdirection beyond the connector section 17 i.

The coil support accommodation space 13 b is disposed inside theinverter housing section 13. The coil support accommodation space 13 baccommodates the coil support 80. The coil support accommodation space13 b is a space in which the coil support 80 is disposed in the innerspace of the inverter housing section 13. The coil support accommodationspace 13 b has an annular shape around the central axis J. The coilsupport accommodation space 13 b overlaps the stator 26 when seen in theaxial direction. The coil support accommodation space 13 b is located onthe inside of the fitting tubular section 17 d in the radial direction.The coil support accommodation space 13 b is a groove-shaped space thatis recessed on one side in the axial direction from the surface of thebottom wall 17 a directed to the other side in the axial direction andextends in the circumferential direction.

The heat conductive sheets 13 c have plate shapes, and a pair of platesurfaces thereof are directed in the axial direction. The heatconductive sheets 13 c are sheet members with elasticity. The heatconductive sheets 13 c have square plate shapes, for example. The heatconductive sheets 13 c are disposed between the first member 16 or thesecond member 17 and the inverter substrate 40 and are brought intocontact with the first member 16 or the second member 17 and theinverter substrate 40. In the embodiment, the heat conductive sheets 13c are disposed between the first member 16 and the inverter substrate 40and are brought into contact with the first member 16 and the invertersubstrate 40. Specifically, the heat conductive sheets 13 c are disposedbetween the top wall 16 a and one plate surface of the invertersubstrate 40 and are brought into contact with the top wall 16 a and theone plate surface of the inverter substrate 40. Although notparticularly illustrated in the drawing, the heat conductive sheets 13 care disposed between a metal portion (metal member) or the like, whichis not illustrated in the drawing, included in the bottom wall 17 a andthe other plate surface of the inverter substrate 40 and are broughtinto contact with the metal portion or the like of the bottom wall 17 aand the other plate surface of the inverter substrate 40 in a case inwhich the heat conductive sheets 13 c are disposed between the secondmember 17 and the inverter substrate 40 and are brought into contactwith the second member 17 and the inverter substrate 40. The heatconductive sheets 13 c are thermally connected to the heat generatingelement 46, which will be described later, of the inverter substrate 40.The heat conductive sheets 13 c have a function of causing heat of theheat generating element 46 to transfer to another member through heatconduction and cooling the heat generating element 46. Configurations,effects, and advantages of the heat conductive sheets 13 c other thanthose described above will be separately described below along withdescription of the inverter substrate 40.

The breather section 14 establishes communication between the inside andthe outside of the housing 11. The breather section 14 is provided atthe brim section 12 b of the motor housing section 12 and is exposed tothe outside of the device from the housing 11 toward the other side inthe axial direction. That is, the breather section 14 is disposed at thebrim section 12 b. The brim section 12 b is covered with the inverterhousing section 13 from one side in the axial direction and is directedto the other side in the axial direction, that is, the side of a memberof the vehicle, which is not illustrated in the drawing, to which theelectric pump device 1 is fixed. Therefore, the brim section 12 b issurrounded by the inverter housing section 13 and members of the vehiclein the axial direction. According to the embodiment, it is possible tocurb direct adhesion of water drops or the like flying due to travelingor the like of the vehicle to the breather section 14. Therefore, themembers in the housing 11 are unlikely to be brought into contact withwater or the like, and functions of the inverter substrate 40, the motor20, and the like are satisfactorily maintained.

The breather section 14 is disposed at a position at which the breathersection 14 does not overlap leg sections 97, which will be describedlater, of a pump cover 95 when seen in the axial direction. According tothe embodiment, since the breather section 14 does not overlap the legsections 97 in the axial direction, inspection for the sealing functionof the housing 11 can be easily performed at an attachment location ofthe breather section 14, that is, from the breather attachment hole 12 iof the brim section 12 b, for example. That is, it is easy to attach ajig or the like of an inspection device, which is not illustrated in thedrawing, to the breather attachment hole 12 i and to remove the jig orthe like therefrom. In addition, it is easy to attach the breathersection 14 to the breather attachment hole 12 i after the inspection.

The breather section 14 is disposed at a position at which the breathersection 14 overlaps the wiring member disposition region 13 a in thebrim section 12 b when seen in the axial direction. In the embodiment,the breather section 14 is disposed on the other side (−Y side) in thewidth direction beyond the central axis J in the wiring memberdisposition region 13 a. Also, the breather section 14 may be disposedon one side (+Y side) in the width direction beyond the central axis Jin the wiring member disposition region 13 a. Since the wiring memberdisposition region 13 a accommodates the wiring members 50, a wide spaceis likely to be secured. According to the embodiment, since the breathersection 14 is disposed at a position at which the breather section 14overlaps the wiring member disposition region 13 a in the brim section12 b when seen in the axial direction, it is possible to take advantageof the vacant space in the housing 11, to optimize disposition ofconfiguration members in the device, and to reduce the electric pumpdevice 1 in size.

Although not particularly illustrated in the drawing, the breathersection 14 is disposed above the center of the electric pump device 1 inthe vertical direction in a state in which the electric pump device 1 isattached to the members of the vehicle. Therefore, it is possible tocurb dropping of the breather section 14 into water. Also,high-temperature air in the housing 11 can be easily caused to escape tothe outside of the device through the breather section 14. Thedisposition of the breather section 14 above the center of the electricpump device 1 in the vertical direction can also be explained using therelative positional relationships between an inlet port 96 a and anoutlet port 96 b, which will be described later, of the pump cover 95.The description will be given later along with description of the pumpcover 95.

The breather section 14 has a breather main body 14 a, a breathertubular section 14 b, claw sections 14 c, and a breather sealing member14 e. The breather main body 14 a has a circular plate shape with aninner space. In the following description, the central axis of thebreather main body 14 a will be referred to as a breather central axisC. The breather central axis C extends so as to be parallel to thecentral axis J, that is, in the axial direction. A radial directionaround the breather central axis C will be referred to as a breatherradial direction. In the breather radial direction, a direction towardthe breather central axis C will be referred to as inward in thebreather radial direction, and a direction away from the breathercentral axis C will be referred to as outward in the breather radialdirection. A circumferential direction around the breather central axisC, that is, turning around the breather central axis C will be referredto as a breather circumferential direction.

The surface of the breather main body 14 a directed to one side in theaxial direction faces the bottom surface of the breather accommodationrecessed section 12 j directed to the other side in the axial directionwith a gap therebetween in the axial direction. The outercircumferential surface of the breather main body 14 a faces the innercircumferential surface of the breather accommodation recessed section12 j with a gap therebetween in the breather radial direction. Thebreather main body 14 a has a portion accommodated in the breatheraccommodation recessed section 12 j.

The breather main body 14 a has breathing holes 14 d. The breathingholes 14 d communicate with the outside of the housing 11. The breathingholes 14 d communicate with the inner space of the breather main body 14a. The plurality of breathing holes 14 d are provided at intervals fromeach other in the breather circumferential direction. The plurality ofbreathing holes 14 d include breathing holes 14 d extending in thebreather radial direction and breathing holes 14 d extending in theaxial direction. The plurality of breathing holes 14 d include breathingholes 14 d opening in the outer circumferential surface of the breathermain body 14 a and breathing holes 14 d opening in the surface of thebreather main body 14 a directed to one side in the axial direction.

The breather tubular section 14 b has a tubular shape extending in theaxial direction. The breather tubular section 14 b is connected to thebreather main body 14 a. The breather tubular section 14 b is connectedto the surface of the breather main body 14 a directed to one side inthe axial direction and extends from the breather main body 14 a towardone side in the axial direction. The breather tubular section 14 b isinserted into the breather attachment hole 12 i. The breather tubularsection 14 b communicates with the breathing holes 14 d through theinner space of the breather main body 14 a. That is, the breathertubular section 14 b communicates with the breathing holes 14 d. Thebreather tubular section 14 b communicates with the inside of theinverter housing section 13 through the through-holes 17 e or the likein the bottom wall 17 a. That is, the breather tubular section 14 bcommunicates with the inside of the housing 11.

The claw sections 14 c project outward in the breather radial directionfrom an end of the breather tubular section 14 b on one side in theaxial direction. The plurality of claw sections 14 c are provided atintervals from each other in the circumferential direction. The clawsections 14 c are brought into contact with the brim section 12 b fromone side in the axial direction. The claw sections 14 c are brought intocontact with the claw support surface 12 k of the brim section 12 b fromone side in the axial direction. That is, the claw sections 14 c arebrought into contact with the claw support surface 12 k. The clawsections 14 c are hooked at the claw support surface 12 k with asnap-fit structure or the like. According to the embodiment, since theclaw support surface 12 k is disposed on one side in the axial directionbeyond the outer surrounding surface 12 l, it is possible to easily workthe claw support surface 12 k with a cutting tool or the like. In thismanner, precision of the position of the claw support surface 12 k inthe axial direction and a worked surface is secured. In addition, it ispossible to stably hook the claw sections 14 c at the claw supportsurface 12 k. In addition, the fixed state of the breather section 14relative to the brim section 12 b is further stabilized.

Here, the breather accommodation wall 17 l accommodates the end of thebreather tubular section 14 b on one side in the axial direction and theclaw sections 14 c and covers the breather tubular section 14 b from oneside in the axial direction. The top wall of the breather accommodationwall 17 l faces the end of the breather tubular section 14 b on one sidein the axial direction and the claw sections 14 c with a gaptherebetween on one side in the axial direction. The circumferentialwall of the breather accommodation wall 17 l faces the end of thebreather tubular section 14 b on one side in the axial direction and theclaw sections 14 c with a gap therebetween from the outside in thebreather radial direction. According to the embodiment, it is possibleto curb direct adhesion of water or the like to electronic componentsand the like in the housing 11 with the breather accommodation wall 17 leven in a case in which water or the like invades the housing 11 fromthe outside of the device through the breather section 14.

The breather sealing member 14 e is, for example, an O ring or the like.The breather sealing member 14 e is brought into contact with the outercircumferential surface of the breather tubular section 14 b, thesurface of the breather main body 14 a directed to one side in the axialdirection, and the inner circumferential surface of the breatherattachment hole 12 i. According to the embodiment, invasion of water orthe like into the housing 11 through a portion between the breathertubular section 14 b and the breather attachment hole 12 i is curbedwith the breather sealing member 14 e. In addition, an attachment stateof the breather section 14 relative to the brim section 12 b is furtherstabilized.

The motor 20 has a rotor 21, a stator 26, and the plurality of bearings35 and 36. The rotor 21 has a shaft 22, a rotor core 23, magnets 24, anda magnet holder 25.

The shaft 22 extends along the central axis J. The shaft 22 extends inthe axial direction around the central axis J. The shaft 22 rotatesabout the central axis J. The shaft 22 is rotatably supported about thecentral axis J with the plurality of bearings 35 and 36. That is, theplurality of bearings 35 and 36 rotatably support the shaft 22. Theplurality of bearings 35 and 36 are, for example, ball bearings or thelike. The first bearing 35 of the plurality of bearings 35 and 36supports a portion located on the other side in the axial directionbeyond the rotor core 23 of the shaft 22. The second bearing 36 of theplurality of bearings 35 and 36 supports a portion located on one sidein the axial direction beyond the rotor core 23 of the shaft 22.

The rotor core 23 is fixed to an outer circumferential surface of theshaft 22. The rotor core 23 has an annular shape extending in thecircumferential direction around the central axis J. The rotor core 23has a tubular shape extending in the axial direction. The rotor core 23is a steel plate laminated body obtained by a plurality ofelectromagnetic steel sheets being laminated in the axial direction, forexample.

The magnets 24 are disposed in an outer side surface of the rotor core23 in the radial direction. The number of magnets 24 provided is aplural number. The plurality of magnets 24 are disposed at intervalsfrom each other in the circumferential direction in the outer sidesurface of the rotor core 23 in the radial direction. Also, a singlecylindrical ring magnet, for example, may be employed for the magnets24.

The magnet holder 25 is provided at the rotor core 23 and holds themagnets 24. The magnet holder 25 fixes the magnets 24 to the rotor core23. The magnet holder 25 is disposed in the outer side surface in theradial direction and the surface directed to the other side in the axialdirection of the rotor core 23. The magnet holder 25 presses the magnets24 from the outside in the radial direction and the other side in theaxial direction. The magnet holder 25 has a portion that is locatedbetween a pair of magnets 24 that are adjacent in the circumferentialdirection and extends in the axial direction and a portion that has anannular shape around the central axis J and is located on the other sideof the magnets 24 in the axial direction.

The stator 26 is disposed on the outside of the rotor 21 in the radialdirection and faces the rotor 21 with a gap therebetween in the radialdirection. That is, the stator 26 faces the rotor 21 in the radialdirection. The stator 26 surrounds the rotor 21 from the outside in theradial direction over the entire circumference in the circumferentialdirection. The stator 26 has a stator core 27, an insulator 28, and aplurality of coils 29.

The stator core 27 has an annular shape around the central axis J. Thestator core 27 surrounds the rotor 21 on the outside of the rotor 21 inthe radial direction. The stator core 27 is disposed on the outside ofthe rotor 21 in the radial direction and faces the rotor 21 with a gaptherebetween in the radial direction. The stator core 27 is a steelsheet laminated body obtained by a plurality of electromagnetic steelsheets being laminated in the axial direction, for example.

The stator core 27 has a core back 27 a and a plurality of teeth 27 b.The core back 27 a has an annular shape around the central axis. Thecore back 27 a has a tubular shape extending in the axial direction. Theouter side surface of the core back 27 a in the radial direction isfixed to the inner circumferential surface of the accommodation tubularsection 12 a. The teeth 27 b extend inward in the radial direction fromthe inner side surface of the core back 27 a in the radial direction.The plurality of teeth 27 b are disposed at intervals from each other inthe circumferential direction in the inner side surface of the core back27 a in the radial direction. The inner side surfaces of the teeth 27 bin the radial direction face the outer side surfaces of the magnets 24in the radial direction with gaps therebetween from the outside in theradial direction.

The insulator 28 is mounted on the stator core 27. The insulator 28 hasa portion that covers the plurality of teeth 27 b. A material for theinsulator 28 is an insulating material such as a resin, for example. Thecoils 29 are attached to the stator core 27. The coils 29 are mounted inthe stator core 27 via the insulator 28. The plurality of coils 29 areformed by winding conductive wires around the respective teeth 27 b viathe insulator 28.

Although not particularly illustrated in the drawing, the plurality ofcoils 29 include a first coil and a second coil. The first coil has afirst conductive wire. The second coil has a second conductive wire thatis different from the first conductive wire. That is, the first coil andthe second coil are in mutually different phases. In the embodiment, themotor 20 has a three-phase motor. The three phases mean a U phase, a Vphase, and a W phase. In the case of the three-phase motor, theconductive wires that form the respective coils 29 in the U phase, the Vphase, and the W phase are different from each other. That is, theconductive wire for the coil 29 in the U phase, the conductive wire forthe coil 29 in the V phase, and the conductive wire for the coil 29 inthe W phase are different from each other. In a case in which the firstcoil is in the U phase, for example, the second coil is in either the Vphase or the W phase. In a case in which the second coil is in the Uphase, the first coil is in either the V phase or the W phase.

The coils 29 have a pair of ends drawn from the coils 29 at both ends ofthe conductive wires of the coils 29. The pair of ends are a first end29 a and a second end 29 b. The ends 29 a an 29 b of the conductivewires of the coils 29 may be referred to as drawn portions of the coils29 instead. The first end 29 a is connected directly to the invertersubstrate 40. The second end 29 b is connected to a neutral point busbar81, which will be described later, of the coil support 80.

The first end 29 a has a first extending section 29 c, a secondextending section 29 d, and a third extending section 29 e (see FIG. 9).The first extending section 29 c extends on one side in the axialdirection from the coils 29. The second extending section 29 d isconnected to the inverter substrate 40 and extends in the axialdirection. The second extending section 29 d is joined to the invertersubstrate 40 using the solder 30. The third extending section 29 econnects one end of the first extending section 29 c in the axialdirection and the other end of the second extending section 29 d in theaxial direction and extends in a direction perpendicularly intersectingthe central axis J. That is, in the embodiment, the first end 29 a ofthe coils 29 has a plurality of bending sections 29 f and 29 g.Specifically, the first end 29 a has a bending section 29 f that islocated at a connecting portion between the first extending section 29 cand the third extending section 29 e and a bending section 29 g that islocated at a connecting portion between the second extending section 29d and the third extending section 29 e. Therefore, vibration is dampedin the process of reaching the second extending section 29 d from thefirst extending section 29 c via the third extending section 29 e whenvibration from the outside or the inside of the device has beendelivered to the first extending section 29 c. Specifically, anamplitude of at least a component in the axial direction in thevibration is reduced, and the vibration is then delivered to theinverter substrate 40. In this manner, a load on the solder 30 thatjoins the second extending section 29 d to the inverter substrate 40 isreduced, and durability of the solder 30 is improved.

At the first ends 29 a, a length Lb of the conductive wire of the thirdextending section 29 e is longer than a length La of the conductive wireof the second extending section 29 d between the inverter substrate 40and the third extending section 29 e. According to the embodiment, theeffect of damping the vibration at the first ends 29 a of the coils 29is further enhanced. Durability of the solder 30 that joins the firstends 29 a to the inverter substrate 40 is further enhanced.

The two first ends 29 a illustrated in FIG. 9 is the first end 29 a ofthe first coil and the first end 29 a of the second coil. That is, thetwo first ends 29 a illustrated in FIG. 9 are in mutually differentphases. The third extending section 29 e of the first coil and the thirdextending section 29 e of the second coil overlap each other when seenin the axial direction, and the third extending section 29 e of thefirst coil an the third extending section 29 e of the second coil aredisposed so as to be separated from each other in the axial direction.According to the embodiment, since the two third extending sections 29 eoverlap each other when seen in the axial direction, it is possible toshorten the length by which each first end 29 a is arranged in thedirection perpendicularly intersecting the central axis J and to curbmutual contact between the first ends 29 a in mutually different phasesin the axial direction. In this manner, the performance of the motor 20is satisfactorily maintained.

The inverter substrate 40 is disposed on one side of the motor 20 in theaxial direction. The inverter substrate 40 is electrically connected toan external power source, which is not illustrated in the drawing, viathe wiring members 50. The inverter substrate 40 is electricallyconnected to the motor 20. The inverter substrate 40 supplies electricpower supplied from the external power source to the stator 26 of themotor 20. The inverter substrate 40 controls a current to be supplied tothe motor 20.

The inverter substrate 40 has a polygonal shape in a plan view of theinverter substrate 40 and has a plurality of corners 45 a, 45 b, . . . .In the embodiment, the inverter substrate 40 has a substantiallypentagonal shape in a plan view of the inverter substrate 40, and theinverter substrate 40 has five corners 45 a, 45 b, . . . . In theembodiment, a corner located on one side (+Y side) of the invertersubstrate 40 in the width direction and also in the projecting direction(+X side) in a plan view of the inverter substrate 40 will be referredto as a first corner 45 a among the plurality of corners 45 a, 45 b, . .. . The first corner 45 a is located on one side in the width directionbeyond the central axis J and also in the projecting direction. Inaddition, the second corner 45 b is a corner located on the other side−Y side) of the inverter substrate 40 in the width direction and also onthe side (−X side) opposite to the projecting direction in a plan viewof the inverter substrate 40. The second corner 45 b is located on theother side in the width direction beyond the central axis J and also onthe side opposite to the projecting direction. A third corner is locatedon the other side in the width direction beyond the central axis J andalso in the projecting direction in a plan view of the invertersubstrate 40. A fourth corner and a fifth corner are located on one sidein the width direction beyond the central axis J and also on the sideopposite to the projecting direction in a plan view of the invertersubstrate 40.

The inverter substrate 40 has a plurality of heat generating elements46, capacitors 47, a drawn section insertion hole 48, terminal insertionholes 41, screw insertion holes 42, and a positioning hole 43. Also, theinverter substrate 40 has a coil connecting region 40 a and a terminalconnecting region 40 b. The plurality of heat generating elements 46 aremounted on the inverter substrate 40 and are disposed at intervals fromeach other. The heat generating elements 46 are, for example, fieldeffect transistors (FETs), a pre-driver, a low-drop out-regulator (LDO),or the like. In the embodiment, the heat generating elements 46 aredisposed on the other plate surface of the inverter substrate 40.

Here, the heat conductive sheets 13 c will be described. In theembodiment, the number of heat conductive sheets 13 c provided is aplural number. That is, the inverter housing section 13 has a pluralityof heat conductive sheets 13 c. The plurality of heat conductive sheets13 c are individually disposed at positions at which the heat conductivesheets 13 c overlap the plurality of heat generating elements 46 in aplan view of the inverter substrate 40. In the embodiment, each heatconductive sheet 13 c overlaps one heat generating element 46 in a planview of the inverter substrate 40. That is, one heat conductive sheet 13c is disposed in a superimposed manner with one heat generating element46. The heat conductive sheet 13 c and the heat generating element 46overlap each other in a one-to-one correspondence when seen in the axialdirection.

As compared with a configuration in which a single heat conductive sheetwith a large area is brought into contact with all the heat generatingelements 46 unlike the embodiment, for example, contact locationsbetween the heat conductive sheets 13 c and the inverter substrate 40are distributed, and the contact area is reduced in the embodiment. Inthis manner, a reaction force of the heat conductive sheets 13 c isreduced, and deformation of the inverter substrate 40 is curbed. Also,performances and the like of electronic components, such as a ceramiccapacitor, for example, mounted on the inverter substrate 40 aresatisfactorily maintained. In addition, durability of the solder 30 thatjoins the first ends 29 a of the coils 29 to the inverter substrate 40is further improved. Durability of the solder 31 that fixes the invertersubstrate 40 to the terminals 51, which will be described later, of thewiring members 50 is further enhanced.

Here, FIG. 10 illustrates a modification example of the heat conductivesheets 13 c according to the embodiment. In the modification example,each heat conductive sheet 13 c overlaps two heat generating elements 46in a plan view of the inverter substrate 40. That is, one heatconductive sheet 13 c is disposed so as to overlap two heat generatingelements 46. Since the contact locations between the heat conductivesheets 13 c and the inverter substrate 40 are still distributed, and thecontact area is still reduced in this case, deformation of the invertersubstrate 40 is curbed.

At least one of the plurality of heat conductive sheets 13 c is disposedbetween the first member 16 and the inverter substrate 40 and is broughtinto contact with the first member 16 and the inverter substrate 40. Inthe embodiment, all the plurality of heat conductive sheets 13 c aredisposed between the first member 16 and the inverter substrate 40 andare brought into contact with the first member 16 and the invertersubstrate 40. According to the embodiment, the heat conductive sheets 13c are brought into contact with the inverter substrate 40 when thesecond member 17 is attached to the motor housing section 12 and thefirst member 16 is attached to the second member 17, that is, whenassembly of the inverter housing section 13 ends. Since it is possibleto support the inverter substrate 40 from both sides in the axialdirection between the first member 16 and the second member 17 when theheat conductive sheets 13 c are brought into contact with the invertersubstrate 40, deformation of the inverter substrate 40 is more easilycurbed.

According to the embodiment, the boss section 17 j supports the otherplate surface of the inverter substrate 40 when the first member 16 isattached to the second member 17 and the heat conductive sheets 13 cpress one plate surface of the inverter substrate 40. Therefore,deformation of the inverter substrate 40 is further curbed. Also, in theembodiment, the boss section 17 j is supported by the bearing holder 17c made of metal in the axial direction. Therefore, the invertersubstrate 40 is stably supported by the boss section 17 j, anddeformation of the inverter substrate 40 is further curbed.

Also, although not particularly illustrated in the drawing, at least oneof the plurality of heat conductive sheets 13 c may be disposed betweenthe second member 17 and the inverter substrate 40 and may be broughtinto contact with the second member 17 and the inverter substrate 40.

The capacitors 47 are disposed on the other plate surface of theinverter substrate 40. The capacitors 47 extend from the other platesurface of the inverter substrate 40 toward the other side in the axialdirection. In the embodiment, the number of capacitor 47 provided is aplural number. The capacitors 47 are disposed in a superimpose mannerwith the coil support 80 when seen in the axial direction.

Drawn section insertion holes 48 penetrate through the invertersubstrate 40 in a plate thickness direction (in the axial direction)thereof. That is, the drawn section insertion holes 48 penetrate throughthe inverter substrate 40. The number of drawn section insertion holes48 provided is a plural number. In the embodiment, the plurality ofdrawn section insertion holes 48 are linearly aligned in a plan view ofthe inverter substrate 40. The plurality of drawn section insertionholes 48 are disposed at an end of the inverter substrate 40 on theother side in the width direction and are aligned in the projectingdirection. The first ends 29 a of the coils 29 are inserted into therespective drawn section insertion holes 48. The first ends 29 a of thecoils 29 are joined to the inverter substrate 40 with the solder 30.

The terminal insertion holes 41 penetrate through the inverter substrate40 in the plate thickness direction thereof. That is, the terminalinsertion holes 41 penetrate through the inverter substrate 40. Thenumber of terminal insertion holes 41 provided is a plural number. Inthe embodiment, the plurality of terminal insertion holes 41 arelinearly aligned in a plan view of the inverter substrate 40. Theplurality of terminal insertion holes 41 are disposed at an end of theinverter substrate 40 in the projecting direction (+X side) and arealigned in the width direction (Y-axis direction). The terminalinsertion holes 41 are disposed at the first corner 45 a. In otherwords, the corner at which the terminal insertion holes 41 are locatedamong the plurality of corners 45 a, 45 b, . . . of the invertersubstrate 40 is the first corner 45 a. Terminals 51, which will bedescribed later, of the wiring members 50 are inserted into therespective terminal insertion holes 41. The terminals 51 are joined tothe inverter substrate 40 with the solder 31.

The screw insertion holes 42 penetrate through the inverter substrate 40in the plate thickness direction thereof. That is, the screw insertionholes 42 penetrate through the inverter substrate 40. The screwinsertion holes 42 are disposed in a superimposed manner with the femalescrew sections of the pillar sections 12 g in a plan view of theinverter substrate 40, that is, when seen in the axial direction. Thenumber of screw insertion holes 42 provided in the inverter substrate 40is a plural number. The respective screw insertion holes 42 are disposedin a superimposed manner with the female screw sections of therespective pillar sections 12 g when seen in the axial direction.

The screw insertion holes 42 are disposed at the plurality of corners 45a, 45 b, . . . of the inverter substrate 40. At least one of theplurality of screw insertion holes 42 is disposed at the first corner 45a. In the embodiment, two screw insertion holes 42 are disposed at thefirst corner 45 a. The terminal insertion hole 41 is disposed betweentwo screw insertion holes 42 at the first corner 45 a in a plan view ofthe inverter substrate 40. The terminal insertion hole 41 is locatedbetween the two screw insertion holes 42 in the width direction.

The positioning hole 43 penetrates through the inverter substrate 40 inthe plate thickness direction thereof. That is, the positioning hole 43penetrates through the inverter substrate 40 in the axial direction. Inthe embodiment, one positioning hole 43 is provided in the invertersubstrate 40. The positioning hole 43 is disposed at a corner of theinverter substrate 40 in a plan view of the inverter substrate 40. Thepositioning hole 43 is disposed at the first corner 45 a. Thepositioning hole 43 is disposed between the terminal insertion holes 41and the outer circumferential end surface of the inverter substrate 40in a plan view of the inverter substrate 40. In the embodiment, thepositioning hole 43 is disposed between the terminal insertion holes 41and the outer circumferential end surface directed to one side of theinverter substrate 40 in the width direction, in the width direction.

The positioning hole 43 faces one screw insertion hole 42 located on oneside in the width direction beyond the terminal insertion holes 41 ofthe two screw insertion holes 42 at the first corner 45 a, with a gaptherebetween in the projecting direction in a plan view of the invertersubstrate 40. That is, the screw insertion hole 42 at the first corner45 a and the positioning hole 43 face one another with a gaptherebetween in a plan view of the inverter substrate 40.

The coil connecting region 40 a is a region in which the ends 29 a ofthe plurality of coils 29 are connected to the inverter substrate 40. Inthe embodiment, the coil connecting region 40 a is disposed on the otherside (−Y side) in the width direction beyond the central axis J in aplan view of the inverter substrate 40. The plurality of heat generatingelements 46 are disposed in the coil connecting region 40 a.Specifically, the plurality of heat generating elements, such as FETs,for example are disposed in the coil connecting region 40 a. Accordingto the embodiment, since the ends 29 a of the plurality of coils 29connected to the inverter substrate 40 and the plurality of heatgenerating elements 46 are disposed so as to be close to each other, itis possible to shorten a wiring pattern of the inverter substrate 40. Inaddition, it is possible to individually and efficiently cool therespective heat generating elements 46 with the respective heatconductive sheets 13 c.

The terminal connecting region 40 b is a region in which the terminals51, which will be described later, of the wiring members 50 areconnected to the inverter substrate 40. In the embodiment, the terminalconnecting region 40 b is disposed on one side (+Y side) in the widthdirection beyond the central axis J and also in the projecting direction(+X side) in a plan view of the inverter substrate 40. The terminalconnecting region 40 b is located at the first corner 45 a. At least oneof the heat generating elements 46 is disposed in the terminalconnecting region 40 b. In the embodiment, the plurality of heatgenerating elements 46 are disposed in the terminal connecting region 40b. Specifically, the heat generating elements such as FETs forprotection from reverse connection or LDOs, for example, are disposed inthe terminal connecting region 40 b. According to the embodiment, sincethe terminals 51 connected to the inverter substrate 40 and the heatgenerating elements 46 are disposed so as to be close to each other, itis possible to shorten a wiring pattern of the inverter substrate 40. Inaddition, it is possible to individually and efficiently cool the heatgenerating elements 46 with the heat conductive sheets 13 c.

The wiring members 50 extend across the outside and the inside of thesecond member 17 through the connector section 17 i. That is, the wiringmembers 50 extend across the outside and the inside of the housing 11.The wiring members 50 are electrically connected to an external powersource, which is not illustrated in the drawing. The wiring members 50are electrically connected to the inverter substrate 40. In theembodiment, the wiring members 50 are made of metal and has a thin andlong plate shape. The wiring members 50 may be referred to as a busbarinstead. The number of wiring members 50 provided is a plural number.

The wiring members 50 have terminals 51 located at ends of the wiringmembers 50. The terminals 51 are provided at the respective wiringmembers 50, respectively. That is, the number of terminals 51 providedis a plural number. The terminals 51 are located at ends on one side,which are disposed inside the housing 11, of both ends of the wiringmembers 50. In the embodiment, each wiring member 50 is a single member,and each terminal 51 forms a part of the wiring member 50. The terminals51 extend in the axial direction inside the inverter housing section 13.The terminals 51 are disposed at the first corner 45 a of the invertersubstrate 40 in a plan view of the inverter substrate 40. The terminals51 are inserted into the terminal insertion holes 41. The terminals 51are connected to the inverter substrate 40 using the solder 31.

The number of screw members 60 provided is a plural number. The screwmembers 60 are inserted into the screw insertion holes 42. The screwmembers 60 have male screw sections. The male screw sections of thescrew members 60 inserted into the screw insertion holes 42 arescrew-cramped to the female screw sections of the pillar sections 12 g.That is, the screw members 60 are inserted into the screw insertionholes 42 and are fixed to the pillar sections 12 g. The screw members 60fix the inverter substrate 40 to the housing 11.

At least two screw members 60 of the plurality of screw members 60 aredisposed in the terminal connecting region 40 b. The terminal 51 islocated between the two screw members 60 in a plan view of the invertersubstrate 40. Specifically, the terminal 51 is disposed between the twoscrew members 60 in the width direction. According to the embodiment, itis possible to curb relative movement between the inverter substrate 40and the terminals 51 due to thermal deformation, vibration, or the likeand to enhance durability of the solder 31 that fixes the invertersubstrate 40 to the terminals 51.

The coil support 80 is located between the motor 20 and the invertersubstrate 40 in the axial direction. That is, the coil support 80 isdisposed between the motor 20 and the inverter substrate 40. The coilsupport 80 supports the first ends 29 a of the coils 29 between themotor 20 and the inverter substrate 40. The coil support 80 guides thefirst ends 29 a of the coils 29 in the axial direction toward theinverter substrate 40. In addition, the coil support 80 supports thesecond ends 29 b of the coils 29. The coil support 80 supports thesecond ends 29 b with a neutral point busbar 81, which will be describedlater. The coil support 80 establishes electric connection among thesecond ends 29 b of the plurality of coils 29 with the neutral pointbusbar 81. That is, the neutral point busbar 81 establishes electricconnection among the plurality of coils 29.

The coil support 80 is accommodated in the coil support accommodationspace 13 b. The coil support accommodation space 13 b, the coil support80, and the bearing 36 are disposed in a superimposed manner when seenin the radial direction. According to the embodiment, it is possible tofurther reduce the electric pump device 1 in size in the axialdirection. The coil support 80 has a capped double-tube shape. The coilsupport 80 has an inner tube, an outer tube, and a ceiling wall. Theinner tube has a cylindrical shape extending in the axial direction. Theouter tube has a cylindrical shape extending in the axial direction andsurrounds the inner tube from the outside in the radial direction. Theceiling wall has a plate shape with a plate surface directed in theaxial direction. The ceiling wall has a substantially annular plateshape. The inner circumferential portion of the ceiling wall isconnected to the inner tube. The outer circumferential portion of theceiling wall is connected to the outer tube. The coil support 80 isdisposed in a superimposed manner with the stator 26 when seen in theaxial direction. The coil support 80 is disposed in a superimposedmanner with the plurality of coils 29 when seen in the axial direction.

The neutral point busbar 81 is made of metal. When the coil support 80is injection-molded, the neutral point busbar 81 is disposed in a mold,which is not illustrated in the drawing. The coil support 80 isinsertion-molded along with the neutral point busbar 81 by filling themold with a molten resin and solidifying the resin. That is, the coilsupport 80 has a portion made of the resin.

The neutral point busbar 81 has coil end holding sections 81 a and aholding section coupling bar 81 b. The coil end holding sections 81 ahold the second ends 29 b of the coils 29. The coil end holding sections81 a have V shapes when seen in the axial direction. The number of coilend holding sections 81 a provided is a plural number. The plurality ofcoil end holding sections 81 a are disposed at intervals from each otherin the circumferential direction. The coil end holding sections 81 a aredisposed between the inner tube and the outer tube of the coil support80 in the radial direction. The holding section coupling bar 81 b isincorporated in the inner tube of the coil support 80. The holdingsection coupling bar 81 b has a plate shape with a plate surfacedirected in the axial direction and extends in the circumferentialdirection. The holding section coupling bar 81 b is connected to theplurality of coil end holding sections 81 a. The holding sectioncoupling bar 81 b establishes electric connection among the plurality ofcoil end holding sections 81 a.

The coil support 80 has a first region 80 a and a second region 80 b.The first region 80 a and the second region 80 b are semi-circularregions, respectively, when seen in the axial direction (see FIG. 7). Inthe first region 80 a, the first ends 29 a of the coils 29 are disposed.In the second region 80 b, the second ends 29 b of the coils 29 and theneutral point busbar 81 are disposed. According to the embodiment, thefirst ends 29 a disposed in the first region 80 a of the coil support 80are connected directly to the inverter substrate 40. That is, it ispossible to dispose the motor 20 and the inverter substrate 40 so as tobe closer to each other in the axial direction since a busbar member forconnecting the ends of the coils to the inverter substrate is not usedin the embodiment unlike the related art. Therefore, it is possible toreduce the electric pump device 1 in size in the axial direction. Also,it is possible to reduce the number of components and to reducemanufacturing costs.

The coil support 80 has a first wall 85 and a second wall 86. The firstwall 85 and the second wall 86 respectively form a part of the ceilingwall of the coil support 80. The first wall 85 is disposed in the firstregion 80 a. The first wall 85 has a plate surface directed in the axialdirection. The first wall 85 has a coil end insertion holes 85 a,extending tubular sections 85 b, and window sections 85 c.

The coil end insertion holes 85 a penetrate through the first wall 85 inthe axial direction. The coil end insertion holes 85 a have circularhole shapes. The first ends 29 a are inserted into the coil endinsertion holes 85 a. The number of coil end insertion holes 85 aprovided is a plural number. The plurality of coil end insertion holes85 a are aligned in the projecting direction (X-axis direction) in thefirst wall 85. The extending tubular sections 85 b have tubular shapesextending on one side in the axial direction from the plate surface ofthe first wall 85 directed to one side in the axial direction. Theinside of the extending tubular sections 85 is a part of the coil endinsertion holes 85 a. The number of extending tubular sections 85 bprovided is a plural number. The plurality of extending tubular sections85 b are aligned in the projecting direction in the first wall 85. Inthe embodiment, parts of outer circumferential surfaces of a pair ofextending tubular sections 85 b that are adjacent to each other areconnected to each other.

According to the embodiment, it is possible to elongate the coil endinsertion holes 85 a on one side in the axial direction by the extendingtubular sections 85 b. Therefore, the coil end insertion holes 85 a canguide the first ends 29 a of the coils 29 to be closer to the invertersubstrate 40. Therefore, connection of the first ends 29 a to theinverter substrate 40 is facilitated. Also, insulation of the first ends29 a is easily secured in accordance with an increase in distance bywhich the coil end insertion holes 85 a guide the first ends 29 a in theaxial direction. Also, the extending tubular sections 85 b are disposedin the tubular section disposition hole 17 m in the bottom wall 17 a.According to the embodiment, it is possible to further reduce theelectric pump device 1 in size in the axial direction.

The window sections 85 c penetrate through the first wall 85 in theaxial direction. The window sections 85 c overlap arrangement sections,which are located on the other side of the first wall 85 in the axialdirection, of the first ends 29 a when seen in the axial direction. Thearrangement sections are, for example, the third extending sections 29e. The number of window sections 85 c provided is a plural number. Inregard to at least one of the plurality of window sections 85 c,arrangement sections of the plurality of coils 29 overlap each other inthe window sections 85 c when seen in the axial direction. According tothe embodiment, the arrangement sections of the first ends 29 a arrangedon the other side of the first wall 85 in the axial direction can beviewed through the window sections 85 c. Therefore, the first ends 29 acan be stably arranged.

The second wall 86 is disposed in the second region 80 b. The secondwall 86 has a plate surface directed in the axial direction. The secondwall 86 has coil end drawing holes 86 a. The coil end drawing holes 86 apenetrate through the second wall 86 in the axial direction. The secondends 29 b are caused to pass through the coil end drawing holes 86 a.That is, the second ends 29 b pass through the coil end drawing holes 86a and are drawn on one side in the axial direction. The number of coilend drawing holes 86 a provided is a plural number. The plurality ofcoil end drawing holes 86 a are disposed at intervals from each other inthe circumferential direction. The coil end drawing holes 86 a and thecoil end holding sections 81 a overlap each other when seen in the axialdirection. The second wall 86 is located on the other side in the axialdirection beyond the coil end holding sections 81 a.

The position of the first wall 85 in the axial direction is on one sidein the axial direction beyond the position of the second wall 86 in theaxial direction. In the embodiment, the first wall 85 supports the firstends 29 a with the coil end insertion holes 85 a and the extendingtubular sections 85 b. Since the first wall 85 is disposed so as to becloser to the inverter substrate 40 in the axial direction than thesecond wall 86, it is possible to stably connect the first ends 29 asupported by the first wall 85 to the inverter substrate 40.

A connecting portion between the neutral point busbar 81 and the secondends 29 b, that is, the coil end holding sections 81 a is disposed onthe other side in the axial direction beyond the plate surface directedto one side of the first wall 85 in the axial direction and is disposedon one side in the axial direction beyond the plate surface directed toone side of the second wall 86 in the axial direction. According to theembodiment, it is possible to reduce the coil support 80 in size in theaxial direction and to reduce the electric pump device 1 in size in theaxial direction.

The pump section 90 is driven by a motive power of the motor 20. Thepump section 90 suctions and ejects a fluid such as an oil. The pumpsection 90 is disposed on the other side of the motor 20 in the axialdirection. The pump section 90 is located at a portion of the electricpump device 1 on the other side in the axial direction. Although notparticularly illustrated in the drawing, the pump section 90 iscontinuous with a flow path for a fluid, such as an oil, provided in adrive device or the like in the vehicle. Therefore, a portion of theelectric pump device 1 on the other side in the axial direction on whichthe pump section 90 is located is fixed to a member of the vehicle.

In the embodiment, the pump section 90 has a trochoid pump structure.The pump section 90 has an inner rotor 91 and an outer rotor 92. Each ofthe inner rotor 91 and the outer rotor 92 has a trochoid tooth shape.The inner rotor 91 is fixed to an end of the shaft 22 on the other sidein the axial direction. Also, relative turning of the inner rotor 91 andthe shaft 22 about the central axis J may be allowed in a predeterminedrange. The outer rotor 92 is disposed on the outside of the inner rotor91 in the radial direction. The outer rotor 92 surrounds the entirecircumference of the inner rotor 91 in the circumferential directionfrom the outside in the radial direction.

The pump cover 95 is fixed to an end of the motor housing section 12 onthe other side in the axial direction and covers the pump section 90from the other side in the axial direction. That is, the pump cover 95is fixed to the housing 11 and covers the pump section 90. The pumpcover 95 is fixed to a member of the vehicle, which is not illustratedin the drawing. The surface of the pump cover 95 directed to the otherside in the axial direction is brought into contact with the member ofthe vehicle. The pump cover 95 has a cover section 96 and leg sections97.

The cover section 96 is disposed in a superimpose manner with the pumpsection 90 when seen in the axial direction and covers the pump section90 on the other side in the axial direction. That is, the cover section96 covers the pump section 90. The cover section 96 has an inlet port 96a and an outlet port 96 b. The inlet port 96 a and the outlet port 96 bare continued to the pump section 90, respectively. The inlet port 96 ais formed of a through-hole that penetrates through the cover section 96in the axial direction. The inlet port 96 a causes a fluid to flow intothe pump section 90. That is, the pump section 90 suctions the fluidfrom the outside of the device through the inlet port 96 a. The outletport 96 b is formed of a through-hole that penetrates through the coversection 96 in the axial direction. The outlet port 96 b causes a fluidto flow out of the pump section 90. That is, the pump section 90 ejectsthe fluid to the outside of the device through the outlet port 96 b. Inthe embodiment, the inlet port 96 a and the outlet port 96 b are alignedin the projecting direction when seen in the axial direction.

A direction from the inlet port 96 a toward the outlet port 96 b whenseen in the axial direction is assumed to be a fluid feeding direction.The breather section 14 is disposed in the fluid feeding directionbeyond the central axis J when seen in the axial direction (see FIG. 2).In the embodiment, the fluid feeding direction is the +X side and adirection that is the same as the projecting direction. Therefore, theprojecting direction (+X side) may be referred to as a fluid feedingdirection instead, and the side (−X side) opposite to the projectingdirection may be referred to as a side opposite to the fluid feedingdirection instead. When the electric pump device 1 is mounted in thevehicle, the inlet port 96 a is disposed on the lower side in thevertical direction beyond a liquid surface of the fluid in order not tocause air entrainment or the like of the fluid, for example. The outletport 96 b is disposed on the upper side in the vertical direction beyondthe inlet port 96 a. That is, the fluid feeding direction is a directionincluding the upper side in the vertical direction. According to theembodiment, since the breather section 14 is disposed on the upper sidein the vertical direction beyond the center of the electric pump device1, it is possible to curb dropping of the breather section 14 in water.Also, it is possible to facilitate escape of hot air in the housing 11to the outside of the device through the breather section 14.

The leg sections 97 are connected to the cover section 96 and aredisposed outside the cover section 96 in the radial direction. The legsections 97 project outward in the radial direction beyond theaccommodation tubular section 12 a. The plurality of leg sections 97 areprovided in an aligned manner in the circumferential direction. Thebreather section 14 is disposed between a pair of leg sections 97 thatare adjacent to each other in the circumferential direction when seen inthe axial direction. Bolt insertion holes 97 a are provided at outerends of the respective leg sections 97 in the radial direction. The boltinsertion holes 97 a penetrate through the leg sections 97 in the axialdirection. The electric pump device 1 is fixed to the member of thevehicle using bolt members, which are not illustrated in the drawing,inserted into the bolt insertion holes 97 a.

Also, the invention is not limited to the aforementioned embodiment, andmodifications and the like of the configuration can be made withoutdeparting from the gist of the invention as will be described below, forexample.

Although the projecting direction and the width direction have beendefined in directions along virtual planes, which are not illustrated inthe drawing, perpendicular to the central axis J in the aforementionedembodiment, the invention is not limited thereto. For example, adirection that is parallel to the projecting direction may be referredto as a “first direction” instead regardless of the direction in whichthe connector section 17 i projects from the circumferential wall 17 b.That is, the first direction is a predetermined direction amongdirections along virtual planes that are perpendicular to the centralaxis J. In this case, one side (+X side) in the first directioncorresponds to the projecting direction, and the other side (−X side) inthe first direction corresponds to the side opposite to the projectingdirection. In addition, the width direction may be referred to as a“second direction” instead. That is, the second direction is a directionthat is orthogonal to the first direction among the directions along thevirtual planes that are perpendicular to the central axis J. In thiscase, one side (+Y side) in the second direction corresponds to one sidein the width direction, and the other side (−Y side) in the seconddirection corresponds to the other side in the width direction. Thefluid feeding direction may be referred to as a “first direction”instead in a similar manner.

In addition to the above description, the respective configurations(components) described in the aforementioned embodiment, modificationexamples, explanatory notes, and the like may be combined withoutdeparting from the gist of the invention, and addition, omission,replacement, and other changes of configurations can be made. Inaddition, the invention is not limited to the aforementioned embodimentand is limited only by the scope of the claims.

What is claimed is:
 1. An electric pump device comprising: a motor; an inverter substrate that is electrically connected to the motor; a housing that accommodates the motor and the inverter substrate; and a pump section that is driven by motive power of the motor, wherein the motor has a rotor that has a shaft extending along a central axis, and a stator that faces the rotor in a radial direction, the inverter substrate is disposed on one side of the motor in an axial direction, the pump section is disposed on the other side of the motor in the axial direction, the housing has a motor housing section that accommodates the motor, an inverter housing section that accommodates the inverter substrate, and a breather section that establishes communication between inside and outside of the housing, the motor housing section has an accommodation tubular section that accommodates the motor, and a brim section that spreads outward in the radial direction from an end of the accommodation tubular section on one side in the axial direction, the inverter housing section is disposed on one side of the brim section in the axial direction and overlaps the brim section when seen in the axial direction, and the breather section is disposed at the brim section.
 2. The electric pump device according to claim 1, further comprising: a pump cover that is fixed to the housing and covers the pump section, wherein the pump cover has a leg section that project outward in the radial direction beyond the accommodation tubular section, and the breather section is disposed at a position at which the breather section does not overlap the leg sections when seen in the axial direction.
 3. The electric pump device according to claim 2, wherein a plurality of the leg sections are provided by being aligned in a circumferential direction.
 4. The electric pump device according to claim 2, wherein the pump cover has a cover section that covers the pump section, the cover section has an inlet port that allows a fluid to flow into the pump section, and an outlet port that allows the fluid to flow out of the pump section, and the breather section is disposed in a flow feeding direction beyond the central axis when seen in the axial direction when it is assumed that a direction from the inlet port toward the outlet port when seen in the axial direction is the fluid feeding direction.
 5. The electric pump device according to claim 1, wherein the inverter housing section has a connector section to which an external power source is connected, the inverter housing section has a wiring member disposition region located between the central axis and the connector section when seen in the axial direction, and the breather section is disposed at a position at which the breather section overlaps the wiring member disposition region in the brim section when seen in the axial direction.
 6. The electric pump device according to claim 1, wherein the brim section has a breather attachment hole that penetrates the brim section in the axial direction, and the breather section has a breather main body that has a breathing hole that communicates with outside of the housing, a breather tubular section that is connected to the breather main body, communicates with inside of the breathing hole and the housing, and is inserted into the breather attachment hole, and a claw section that projects outward in a breather radial direction, which is orthogonal to a breather central axis, from an end of the breather tubular section on one side in the axial direction and is brought into contact with the brim section from one side in the axial direction.
 7. The electric pump device according to claim 6, wherein the inverter housing section has a first member that faces one plate surface of a pair of plate surfaces of the inverter substrate, and a second member that faces the other plate surface of the pair of plate surfaces, the second member is disposed between the motor housing section and the first member, the second member has a bottom wall that faces the other plate surface of the inverter substrate, the bottom wall has a breather accommodation wall that is recessed on one side in the axial direction from a surface directed to the other side of the bottom wall in the axial direction, and the breather accommodation wall accommodates an end of the breather tubular section on one side in the axial direction and the claw section and covers the breather tubular section from one side in the axial direction.
 8. The electric pump device according to claim 6, wherein the brim section has a claw support surface, which is disposed on a surface directed to one side of the brim section in the axial direction, with which the claw section is brought into contact, and an outer surrounding surface that is disposed on the surface directed to one side of the brim section in the axial direction and surrounds the claw section support surface from outwards in the breather radial direction when seen in the axial direction, and the outer surrounding surface is located on the other side in the axial direction beyond the claw support surface. 